Key lamp socket



will 5, 1950 G. B. BENANDER 2,505,l

KEY LAMP SOCKET Filed June 24, 1948 If by Irwvrvtowm Geowgg@ BBenamdQm Patented Apr. 25, 1950 KEY LAMP SOCKET George B. Bcnamier;` Oaklawn, It. I, assigner to` Monowatt Incorporated, a corporation of. Connecticut Application June 24, 1948, Serial No. 34,895

The lpresent invention relates to key lamp sockets.

One object of the invention isY to provide an im.- proved switch contact arrangement for key lamp sockets which is` unusually compact so as to permit the switch structure to be ass-embled in a lamp socket casing of small dimensions.

A further object is to provide a switch mechanisrn which is simple in structure, easily assembled, and readily adapted to be assembled for either a single lament lamp` or for a two filament lamp,` i. e.- a higl'r1ow'1`amp.

For a consideration of what I believe to be novell and my invention, attention is directed` to the following specication and to the' claims appended thereto.

In the drawing, Fig. 1 is a sectional view of a lamp socket embodying my invention; Fig. 2` is a face viewA of one portion of the lamp socket casing' showing theV switch and contact. members assembled therein for a two iilament lamp; Fig; 3' is an exploded' View of the lamp socket shown in Figs. l: and 2; Fig. 4 is a detailed sectional View illustrating the manner in which the conductors of the cordV are connected to the. lamp socket; Fig, 5 is a View similar to Fig. 2` showing a lamp socket for a single filament lamp; and Fig.. 6- is a perspective View of the contact members shown in Fig. 5;

Referring to the drawing, the socket casing is split longitudinally to provide two complementary portions or halves I` and 2. For convenience, the portion i may be termed the base and the portion 2 the cov-er, since in assembling the socket, the several Contact parts are assembled portion l, after which portion 2 is positioned over it. The casing parts are connected together by a blind screw 3, the ends of which have friction fits in sockets 4 and 5 in the respective parts, and by an internally threaded collar Shaving tapped openings to receive screws L As shown el'early in Figs, i and 2, base i is provided with transverse partition walls B, 9, and IU which serve to dei-lne a wiring cavity H, a switch cavity l2, and a screw shell cavity i3; cover 2 is provided with similar walls I4, l5, and Hi providing corresponding complementary cavities Il, i8, and it, so that when the casing parts are fastened together, there is provided a wiring chamber formed by cavities H and il, a switch. chamber formed by cavities l2 and I8, and a screw shell chamber formed by cavities i3 and I9.

This invention has to do particularly with the switch chamber and the construction and' ar rangements of the contacts therein whereby I am enabled to economize in the space required for the switch members, so as to keep 'the over-- all size of the lamp socket to a minimum; and at the same time provide a construction whereby4 in the same casing I am enabled` in a simple manner and with few changes in contact parts to providela lamp socket for either a two lament lamp or a single filament lamp.

Atl the central portion of switch cavity l2 in base i are wallsv which dene a center post 2l) on opposite sides of which are switch contact cavities ZI' and 22. Post 2U has a passage through it for a switch stem 23, on the outer end of which is a switch operating button 24. On the inner end of'stem 25;'- is a contact carrier comprising a disk 25 of insulating material having spaced ratched teeth which define two opposed longer ratchet surfaces 26 and two opposed shorter ratchet surfaces 2l, the surfaces 2E covering arcs of thel disk approximately twice as long as the surfaces 2l. Carried by disk 25 is a bridging contact member 28 which extends across the underside of disk 25 and has its two ends bent at right angles to cover ratchet surfaces 26. Disk 25 has a round opening through which stem 23 extends and a rectangular recess in which a rectangular head 29V on the inner end` of the stem 23 ts to provide aconnection between the disk and the stem. The contact carrier is in contact with and turns on the end of post 2t. It is positioned with respect to the post by a collar 3E) on contact member 28 which extends into a recess in the inner end` of the post (see Fig. 1).

In contact cavities 2l and Z2 are V-shaped spring switch contacts 3|y and 32, the closed ends of the. Vs4 being. at the bottoms of the cavities and the open ends being adjacent the contact carrier.. The outer arm of contact 3l is :attached to a lamp contact strip 33;. itsv inner` arm engages the edge of the contact carrier. The outer arm of contact 32 is attached to a contact strip 34; its inner arm engages the edge of the contact carrier. The arms ot contactsBl and 32 which engage the contact carrier are spring pressed against it due to the inherent resiliency of the material from which the contacts are ma-de. rihe ends of the arms which are in engagement with the edge of the contact carrier are curved somewhat as shown clearly in Fig. 2, so as to conform to the contour of the outer surfaces of the ratchet teeth to eifect good engagement with the contact 28. It will be noted that contacts; 3i and 32 are positioned at right angles to contact strips 33- and 35 and that the free arms of contacts 3i and 32 stand at right angles to the plane of the contact carrier so that the periphery of disk 25 engages the sides of the arms adjacent to their outer ends. This arrangement is Ione important feature of my invention since by such arrangement I am enabled to provide a more compact structur-e than heretofore while at the same time providing a contact arm long enough to give the desired resiliency for the contact arm. The arrangement is of advantage also in assembling the switch parts since the V-shaped contacts fit readily in the contact cavities 2l and 22 and tend to remain there.

Contact strip 33 is positioned edgewise in a notch in wall I with its free end projecting into screw shell cavity I3 Where it forms a contact for a two-filament lamp. It is provided with notches 35 in its edges for locking over wall i and over the corresponding wall I5 of cover I. Contact strip 34 extends across wiring cavity Il and is positioned edgewise in notches in walls 9 and 8. It is provided with notches 8l in its edges for locking over wall 9 and over the corresponding wall I5 of cover I. In the screw shell cavity is a center lamp contact 38 integral with which isa spring switch contact 39, the face end oi which engages the edge of the switch contact carrier. It is positioned edgevvise in a notch in Wall It and a corresponding notch in wall I6 of cover l. Also in the screw shell cavity is a screw shell 40 to which is attached a Contact strip 4I which extends edgewise alo-ng the side of the casing as shown in Fig. 2, its end extending across wiring cavity Il. It is positioned edgewise in notches in walls Iii, 9, and S and in corresponding notches in Walls I6, I5, and l!! of cover 2. Separating contact strip 4I and contact 3i Vis a post 42 integral with base I. A

The ends of conductor wires are attached to contact strips 34 and II in Wiring cavity II. Insoiar as the present invention is concerned, they may be attached in any suitable manner. In the present instance, a cord i3 is shown as having its bared conductor ends it attached to the contacts by being wedged in slots 135 defined by Walls in cover I as shown in Fig. 4.

Cover 2 is provided with a center post 46 which is in alignment with post 23 and serves, when the structure is assembled, to hold the contact carrier in position. Post 46 has a bore in which the inner end of switch stem 23 is positioned to assist in keeping the contact carrier centered.

In assembling, base I with collar i5 fastened therein by the one screw 1, may be placed in a suitable Xture and the several switch and contact elements positioned therein, stem 23 with disk 25 thereon being dropped through post 20, one end of screw 3 being forced into socket 4, and the bared ends of the conductors being placed across the edges of contact strips 35 and 4I all as shown in Fig. 2. After the parts are assembled in base I, cover 2 is positioned over the base, the other end of screw 3 being forced into socket 5 and the other screw 'I threaded into collar 6. Preferably, the arrangement is such that this screw 1 passes entirely through collar '5 to serve as a setscrew for a pipe threaded into collar E. When the cover I is positioned on the base, slots 45 are forced down over contact strips 34 and 4I, clamping the conductor ends as shown in Fig. 4.

In Fig. 2, the switch is shown in open position, since switch contacts 3i and 32 are in engagement with insulating surface 21. When the contact carrier is turned counterclockwise one step, contacts 3I and 32 will be brought into ensagement with bridging contact member 28 and since contact 39 remains in engagement with contact member 28, a circuit will be closed through both filaments of a two iilament lamp in the lamp socket. When the contact carrier is turned another step, contact 39 will be out of engagement with bridging contact member 28, leaving only contacts 3| and 32 in engagement therewith so that only one lamp filament will be connected in circuit. When turned another step, the switch will be again in its open position.

For a single iilament lamp socket, the same casing parts may be used, it being necessary merely to substitute for switch contact structures 3l, 33 and 38, 39, a switch contact structure comprising center contact 48 and V-shaped switch contact 49 as shown in Figs. 5 and 6. Otherwise, the structure may be the same as that already described. Accordingly, in Figs. 5 and 6, reference characters the same as those of Figs. 1 to 4 have been applied to corresponding parts. From the description already given the structure and operation of the lamp socket for a single lament lamp will be clear.

Certain features disclosed in this application are not claimed herein as they form subject matter claimed in my earlier led applications Serial No. 638,776, illed January 3, 1946, now Patent No. 2,457,521, December 28, 1948; Serial No. 718,166, filed December 24, 1946, now Patent No. 2,483,120, September 27, 1949; and Serial No. 8,470, iiled February 14, 1948.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. In a lamp socket, a casing split longitudinally to provide complementary base and cover portions, walls in said portions which deiine complementary switch cavities, walls in the switch cavity of the base portion which denne a Center post and a contact cavity on each side of the post, a ratchet type contact carrier positioned to turn on the inner end of said post, strip contacts extending longitudinally of the casing having ends which terminate in the switch cavity, and V-shaped switch contacts positioned in said contact cavities with their closed ends at the bottoms of the cavities, the outer arm of each V-shaped contact being connected to one of said strip contacts, the inner arm of each V-shaped contact being positioned at right angles to the plane of the contact carrier with the side of its free end in engagement therewith and said carrier having a bridging contact adapted, when said carrier is operated, to control the interconnection oi said strip contacts.

2. In a lamp socket, a casing split longitudinally to provide complementary base and cover portions, walls in said portions which dene complementary switch cavities, walls in the switch cavity of the base portion which dene a contact cavity on each side of the base, a ratchet type contact carrier in the switch cavity, strip contacts extending longitudinally of the casing having ends which terminate in the switch cavity, and switch contacts connected to said ends and extending at right angles to the plane of the contact carrier positioned in said contact cavities with the sides of their free ends in engagement with the edge of the contact carrier said carrier having a bridging contact adapted, when said carrier is operated, to control the interconnection of said strip contacts.

3. In a lamp socket for a two filament lamp, a casing split longitudinally to provide complementary base and cover portions, Walls in said portions which dene complementary switch cavities, walls in the switch cavity of the base portion which dene a contact cavity on each side of the base, a ratchet type contact carrier in the switch cavity having opposed wide and narrow ratchet teeth on its edge and a bridging contact on the faces of the wide teeth, three switch contacts having contact ends in the switch cavity in engagement with the edge of said contact carrier, two of said contacts being positioned in said contact cavities at right angles to the plane of the contact carrier, and means connecting two of said switch contacts to contact ends to be engaged by the contact terminals of a two filament lamp said bridging contact being adapted, when said carrier is operated, to control selectively the interconnection of said switch contacts and thereby to control selectively the energization of said lamp filaments.

4. A rotary switch comprising a casing split to provide base and cover portions, a recess in said casing portions forming a switch cavity, a ratchet type contact carrier in the switch cavity having opposed ratchet teeth in its edge and a bridging contact on the edge faces of alternate teeth, two switch contacts formed of strip spring metal reversely bent into a V-shape and being positioned in said cavity on opposite sides of said carrier with their closed ends at the bottom of the cavity, the outer arm of each V- shaped contact having circuit connecting means secured thereto and the inner arm of each V- shaped contact being positioned at right angles to the plane oi said contact carrier with the side of its free end in engagement with a ratchet tooth face thereof, said bridging contact being adapted, upon rotation of the carrier, to control the interconnection of said contacts. 5. A three position rotary switch comprising a casing split to provide base and cover portions,

a recess in said casing portions forming a switch cavity, a ratchet type contact carriery in the switch cavity having opposed wide and. narrow ratchet teeth in its edge and a bridging contact on the edge faces of the wire teeth, two switch contacts formed of strip spring metal reversely bent into a V-s'hape and being positioned in said cavity on opposite sides of said carrier with their lclosed ends at the bottom of the cavity, the outer arm of each V-shaped contact having circuit connecting means secured thereto and the inner arm of each V-shaped contact being positioned at right angles to the plane of said contact carrier with the side of its free end in engagement with a ratchet tooth face thereof, and a third switch contact having a contact end in said cavity and positioned in engagement with a ratchet tooth face thereof and spaced less than the width of said wide ratchet teeth from one of said V-shaped contacts, said bridging contact being adapted upon rotation of the carrier, to cont-rol selectively the interconnection of said switch contacts.

GEORGE B. BENAN'DER..

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 723,510 Zielinski Mar. 24, 1903 1,684,268 Hays Sept. 11, 1928 2,079,800 Grant May 11, 193'7 2,113,218 Nielsen Apr. 5, 1938 2,127,370 Sammut Aug. 16, 1938 2,217,395 Wertzheiser Oct. 8, 1940 2,329,162 Perkins Sept. 7, 1943 

